“Aristotle's successor as director of the Lyceum was Theophrastus, his friend and disciple; Eudemus, another of the Stagirite's important disciples should also be mentioned. Other philosophers belonging to the Peripatetic school were: Aristoxenus, Dikaiarchos, Phanias, Straton, Duris, Chamaeleon, Lycon, Hieronymus, Ariston, Critolaus, Phormio, Sotion, Hermippus, Satyrus and others. Straton even succeeded Theophrastus as director of the Lyceum but his name and those of the other Peripatetics of Aristotle's old school should not be considered in a history of logic as (...) they were mainly concerned with history and the natural sciences. Theophrastus rejoiced in an enormous prestige at this time and for long afterwards. Diogenes Laertius attributes a tremendous number of works to him. Of them a signiﬁcant proportion are writings on logic: Analytica Priora (3 books); Analytica Posteriora (7 books); Analysis of Syllogisms (1 book); Summary of the Analytic s (1 book); Polemic on the Theory of Euristic Arguments. On Deﬁnition (1 book); The First Premises (18 books); The Sophisms (2 books); On the Solution of Syllogisms (1 book); Topics (2 books); On Artless Demonstrations (1 book); On Negation (1 book); On Intellect (1 book); Classiﬁcations (2 books); On Entymemes (1 book); On the Appreciation of Syllogism (1 book); On Lies and Truth (1 book); Argumentations (2 books); Theses (3 books); On Deﬁnition (2 books); On the Data of Problems (1 book); On the Liar (3 books); Preface to the Topics (1 book); On Arguments proper (1 book); Speciﬁcations on The Texts of Syllogisms (1 book). Eudemus also wrote some treatises on logic, concerning which some information has come down to us; Ammonius, in his Commentary On Aristotle's Categories attributes to him a writing on The Analytics -- 'Analitika', and another On Expressions -- Peri lexeos, in which he deals with the grammatical and logical functions of the sentence. The commentator David in Prolegomena to Isagoge by Porphiry also mentions these works.. (shrink)

ABSTRACT: This paper traces the evidence in Galen's Introduction to Logic (Institutio Logica) for a hypothetical syllogistic which predates Stoic propositional logic. It emerges that Galen is one of our main witnesses for such a theory, whose authors are most likely Theophrastus and Eudemus. A reconstruction of this theory is offered which - among other things - allows to solve some apparent textual difficulties in the Institutio Logica.

In the "Doxographi Graeci" the preferred short heading of Aët. 2.31 (Greek text below, p. 28) is 'On Distances', though ps.Plutarch has a long heading. This chapter is about the distances of the sun and moon from each other and from the earth (lemmas 1 to 3, in both ps.Plutarch and Stobaeus), and of the real or apparent shape of the heaven relative to its distance from the earth (lemmas 4 and 5, Stobaeus only). Parallels from Ioann. Lydus and Theodoret (...) for what is in ps.Plutarch are given by Diels in apparatu. To the best of my knowledge it has not been noticed that a version of ps.Plutarch's text is preserved in a scholium on the "Almagest", which constitutes our earliest evidence for the text. The correctness of Diels' reconstruction is questionable. Though certainty, naturally, is beyond our reach it is quite possible that these two sets of lemmas represent two distinct Aëtian (or proto-Aëtian) chapters. These may have been coalesced by Stobaeus (or Aëtius), while ps.Plutarch abridged the second (or the two final lemmas) away. These considerations necessitate an inquiry into the parallels that are available, including material from an introduction to Aratus. The vexing question of short versus long(er) chapter headings is also relevant in this context. Furthermore, the contrasting views regarding cosmic distances are not only a feature of the Placita literature with a distant origin in Aristotle, but also, apparently, of the commentary literature on Plato's "Timaeus". Arguably in a passage in Plutarch's "De facie" these two traditions intersect. Finally, a case can be made out for Eudemus not Theophrastus as an intermediary source of Presocratic astronomical data in the Placita. (shrink)